I, too, try to be careful. I believe in standards of quality for what I vape. On websites that sell, wherever they are located, I look for seals of approval, quality statements, ingredient standards, etc.
I know that vendors can lie, but, it is a start.
I listen to people here and their recommendations, some for flavors, but also for vendor recommendations.
I rarely buy from a B&M that has any kind of "dirty".
On vender websites, I look for pictures of the establishment.
I notice how e-juice is packaged
I take notes, a lot of notes.
Hope helps.
